Pole sander

ABSTRACT

A pole sander having a rectangular sander plate which removeably holds one or more sheets of sandpaper by a pair of clamp assemblies positioned at opposite ends of the sander plate. The sander plate is attached to the upper end of a pole by a universal joint having elements arranged to permit the pole to assume a position close to parallel with the drywall surface being sanded.

FIELD OF THE INVENTION

The present invention relates to sanders and more particularly to an improved pole sander of the type used for sanding joints in drywall constructed walls and the like.

BACKGROUND OF THE INVENTION

Drywall constructed walls are used in the construction industry for constructing the interior walls and ceilings of houses and buildings. The drywall boards are nailed, screwed or otherwise fastened to studs to form such interior walls. This method of construction leaves intersecting joints and screw or nail holes which are filled with joint compound and require sanding to complete the installation process.

The present invention relates to pole sanders for sanding drywall constructed walls. Prior art pole sanders usually employ some type of universal joint in order to permit the flat sandpaper surface, which is generally laid over a foam pad laminated to the flat back surface of the sander plate and secured by clamps on the top surface at opposite ends, to conform to the plane of the drywall wall or ceiling surface against which the sandpaper is applied during the sanding operation. In utilizing pole sanders, the user is generally a considerable distance away from the surface to be sanded at the other end of the pole as the pole operator applies sanding pressure to the drywall surface being sanded. Prior art pole sanders, although satisfactory, have several undesirable features which affect their function. For example, the universal joint in conjunction with the clamp design, often acts as an impediment in directing the pole as close as possible to an angle parallel to the wallboard surface in reaching for corners or the like. The universal joint of prior art pole sanders often do not swivel in an efficient manner, thereby requiring the operator to exert careful attention to obtain a satisfactory smoothing of the wallboard surface. Another disadvantage of some prior art sanders is that they utilize wing nuts, threaded studs and stamped or cast clamps of varying designs located at opposite ends of the sander block to removably secure a sandpaper sheets to the sander block. With this arrangement, considerable time can be required to change a worn sandpaper sheet.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a drywall pole sander that overcomes the disadvantages of prior art drywall pole sanders. My pole sander of the present invention includes a sander plate that is connected to one end of a pole by means of a unique universal joint in a manner that permits smooth swiveling of the sander plate relative the pole. Additionally, the special relationship of the sander plate, the sandpaper clamp design and the pole permit the pole to assume a position close to parallel with the drywall surface being sanded when reaching for corners or the like during a drywall sanding operation. Another object of my drywall pole sander embodying the present invention is to provide a pair of clamp assemblies for removably securing a sandpaper sheet to the opposite ends of the sander plate thereby reducing the time required to change sandpaper sheets as compared certain prior art pole sanders. Also, such clamp assemblies can support a plurality of sandpaper sheets on the sander block whereby the sander operator does not need to leave his worksite to obtain replacement sandpaper sheets.

These and other advantages of the pole sander of my present invention will become apparent from consideration of the following detailed description when taking in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a prospective view of a pole sander embodying the present invention during the sanding of a drywall ceiling.

FIG. 2 is a side elevational view of such pole sander wherein the pole sander is shown during the sanding of a vertical wall.

FIG. 3 is a top plan view of the sander plate of my pole sander.

FIG. 4 is a vertical sectional view taken along line 4/4 of FIG. 3.

FIG. 5 is a vertical sectional view taken along line 5/5 of FIG. 4.

FIG. 6 is a vertical sectional view taken in enlarged scale along line 6/6 of FIG. 3.

FIG. 7 is a vertical sectional view taking in an enlarged scale along line 7/7 of FIG. 6.

FIG. 8 is a broken top plan view taken along line 8/8 of FIG. 7 showing a sandpaper clamp assembly of my pole sander.

FIG. 9 is a broken top plan view of my pole sander showing a universal joint interposed between the sander plate and the pole of my pole sander.

FIG. 10 is a vertical sectional view taken in enlarged scale along line 10/10 of FIG. 9.

FIG. 11 is an enlarged vertical section view of the encircled area designated 11 in FIG. 4.

FIG. 12 is a vertical sectional view taken along line 12/12 of FIG. 9.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to the drawings, a preferred embodiment of a pole sander embodying my present invention includes a rectangular sander plate SP which is connected to the upper end of a pole P by a universal joint assembly U. The opposite ends of the sander plate SP are provided with a pair of like, mirror-image clamp assemblies C and C-1 for releaseably securing one or more sheets of sandpaper S to the underside of a foam base pad R rigidly attached to the underside of sander plate SP, as by an adhesive (not shown). In the use of my pole sander the operator of the tool will manipulate the pole P so that the sandpaper S will slidingly and frictionally engage a desired area of a sheet of wallboard W or the like.

More particularly, the sander plate SP may be cast of a rigid material such as aluminum or plastic. An annular aperture 10 is cast into the plate coaxial with aperture 11 die cut in base pad R. The top of such sander plate is cast with a pair of integral longitudinally extending ribs 20 and 21 of like configuration. The mid portion of the ribs 20 and 21 are enlarged and cast with horizontally aligned bores 22 and 24 that receive roll pins 25 inserted into the opposite ends of a universal joint 26 that rigidly extends between the free ends of the universal joint assembly U. Universal joint 26 extends transversely to the longitudinal axis of sander plate SP. The universal joint 26 may be fabricated of zinc, aluminum, or plastic and is centrally cast with a tubular swivel journal 28 which extends transversely to the longitudinal axis of the universal joint 26 (see FIGS. 3 and 9). The swivel journal 28 is cored through to allow a roll pin 30 to be inserted into cored holes 31 formed in the legs 33 and 33-1 at the open end of an elongated U-shaped yoke 34. A threaded yoke 36 is threaded at 37 its end opposite yoke 34 to be removably connected to the top of pole P. The aforementioned yoke 34 is integrally cast on the threaded yoke 36 on the end thereof opposite threads 37. (See FIGS. 9 and 10). It should be noted that the swivel 26, yoke 34, swivel journal 28 and roll pins 25 and 30 define the aforementioned universal joint assembly U of my pole sander. The universal joint assembly U is preferably centered with respect to the longitudinal and transverse axes of the sander plate SP. The threaded yoke 36 may be fabricated in zinc, aluminum or plastic. With the aforedescribed arrangement of parts of the universal joint assembly U, the yoke 34 is free to rotate horizontally relative to the sander plate SP to permit the pole P to assume a position substantially parallel to the drywall surface W being sanded (FIG. 2). Also, sander plate SP can be rotated about a horizontal axis transverse to the longitudinal axis of universal joint 26 and the sander plate.

The clamp assemblies C and C-1 of my pole sander each include a cam lever 39 supported on aligned pair of ears 40 integrally cast on the upper surface of the sander plate SP by means of a roll pin 42 (FIG. 11). The portion of each cam lever 39 proximate the adjacent end of the sander block is cast with a cam surface 44. Each clamp assembly C and C-1 also includes a spring steel clamp 50 having a round depression 51 its inner end anchored within cored hole 52 cast in the upper surface of sander plate SP (FIGS. 4, 6 and 11). The outer end of each spring steel clamp 50 is formed with depending lip 54 that is engageable with a sheet of sandpaper S (FIG. 11). Referring now to FIG. 4, cam lever 39 of the clamp assembly C shown at the left-hand side of sander plate SP is disposed at a raised position under the influence of spring steel clamp 50. Clamp assembly C-1 located at the right-hand side of sander plate SP is shown with its cam lever handle 39 pivoted clockwise relative to the sander block whereby its cam surface 44 has engaged the spring steel clamp 50 and forced such spring steel clamp downwardly with lip 54 having been moved into tight engagement with the upper surface of the sandpaper sheet positioned upon the right-hand edge of sander plate SP.

Referring to FIG. 11, a sheet of sandpaper S is shown encircling the sander plate SP with clamp assembly C-1 removably securing the right-hand edge of sandpaper S to the sander plate. When both clamp assemblies C and C-1 have been engaged with opposite ends of the sandpaper sheet S encircling the sander block, such sandpaper will be firmly secured to the sander plate and its foam pad R by the downward pressure applied to the opposite ends of the sandpaper sheet S where the ends of such sheet overlap the upper side edge of the sander plate SP. It should be particularly noted that a stack of sandpaper sheets (not shown) can be releasably stored on the sander plate SP rather than a single sandpaper sheet. With this arrangement the pole sander operator will have a supply of replacement sandpaper sheets readily available at his worksite.

In the use of my aforedescribed pole sander, clamp assemblies C and C-1 will be manipulated to releaseably secure a sheet of sandpaper to the sander plate SP and its foam pad R. Pole P can then be utilized to manually apply sliding frictional pressure to the surfaces of the drywall defining the ceiling and walls of a building.

It should be noted that the universal joint assembly of my present invention is more streamlined and affords smoother operation than the prior art pole sanders, such as shown in Hanke U.S. Pat. No. 4,885,876, for example. Note also in this regard that yoke 34 include legs 33 and 33-1 of sufficient length to straddle the universal joint 26 when pole P is pivoted to a position almost paralleling sander plate P (FIG. 10).

Additionally, the universal joint of my present invention provides a much lower center of gravity as compared to conventional prior art pole sanders. Lowering the center of gravity reduces the potential for “flipping” of the sander plate. Flipping occurs when the pole operator positioned at the distal end of the pole opposite the sander plate SP is disposed in a substantially parallel relationship to the flat back surface of the sander plate, since at that time the force required to frictionally remove excessive drywall joint compound from an unfinished joint will tend to tip one edge of the sander plate counter to the direction of force being applied by the pole. Once the edge digs into the drywall the sander plate can flip resulting in damage to the unfinished drywall surface. Repairing the resulting damage adds time and cost to the job in an already competitive environment.

The structure of my universal joint assembly also simplifies the functional operation of the universal joint assembly by incorporating two major components as opposed to the three required by some prior art pole sanders, ie Hanke U.S. Pat. No. 4,885,876. This allows my pole sander to have the lowest possible center of gravity while still allowing for a nearly parallel operation of the sander plate in relation to the pole. This is accomplished by inverting the yoke 34 thereby providing the necessary clearance to avoid interfering with the projections on the sander plate, and also extending the bottom of the yoke 34 into the upper portion of aperture 10 (FIG. 4).

Yet another advantage of my universal joint design is the ability of the sander plate to swivel freely with respect to the pole.

It is to be understood that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention, to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. A pole sander for sanding a drywall surface, comprising: a pole; a sander plate having clamps that releasably secure one or more sheets of sandpaper to the sander plate; a universal joint interposed between one end of the pole and the sander plate, said universal joint including a swivel connector attachable to the pole at one end and formed with an elongated inverted U-shaped yoke at its other end; pole attachment means at one end of the yoke wherein the yoke includes legs of sufficient length to straddle the universal joint when the pole is pivoted to a position almost paralleling the sander plate; a swivel element extending across the open end of the yoke; and a swivel journal rotatably extending at a right angle away from the center of the swivel element at an angle normal to the swivel element.
 2. A pole sander as set forth in claim 1, wherein an annular aperture is formed on the sander plate to receive the lower end of the yoke when the pole is pivoted to a position almost paralleling the sander plate.
 3. A pole sander as set forth in claim 1, wherein a foam base pad is attached to the underside of the sander plate, and such pad is formed with an aperture opposite the sander plate aperture.
 4. A pole sander as set forth in claim 1, wherein the upper surface of the sander plate is formed with a pair of like parallel ribs having their mid-section spaced above such upper surface and formed with aligned horizontal bores that support the opposite ends of the swivel element.
 5. A pole sander as set forth in claim 3, wherein an annular aperture is formed on the sander plate to receive the lower end of the yoke when the pole is pivoted to a position almost paralleling the sander plate.
 6. A pole sander as set forth in claim 3, wherein the upper surface of the sander plate is formed with a pair of like paralleled ribs having their mid-section spaced above such upper surface and formed with aligned horizontal bores that support the opposite ends of the swivel element. 